Defence, nuclear & energy technology

Answer: (c) 1 and 2 only

Stealth technology aims to make an aircraft or ship nearly invisible to radar by shaping it and coating it with materials that absorb radar, so it sends back a very small echo. Coatings are meant to cut the returned signal, not to increase scattering.

• ✓ 1. Stealth designs aim for a very small radar cross-section, and radar-absorbing materials are a standard part of it. The B-2's stealth features include radar-absorbing materials, and its radar cross-section is reported to be like that of a small bird.
• ✓ 2. UPSC's official key treats this statement as correct; we could not confirm the detail from an official source, so we do not explain it here.
• ✗ 3. Britannica notes that surface materials and coatings are used to absorb radar transmissions and reduce reflections to the enemy's radar receiver. Increasing scattering would make the object easier to detect, which defeats the purpose.

Remember · Stealth = very small radar cross-section using shaping and radar-absorbing coatings; coatings reduce, never increase, the radar echo.

Question and answer: UPSC's provisional GS Paper I (2026, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 1 Oct 2026 (how we verify). Permalink · Report an error

Answer: (b) 2 and 3 only

A drone swarm is a large group of small unmanned systems that work together on a mission, and GPS spoofing is one of the recognised counter-UAS techniques.

• ✗ 1. UPSC's official key treats this statement as incorrect; we could not confirm the detail from an official source, so we do not explain it here.
• ✓ 2. A swarm is a group of drones that act together on one mission (PIB, DARPA). UPSC's official key treats the statement as correct; we could not confirm the rest of the detail from an official source, so we do not explain it here.
• ✓ 3. The NATO Science and Technology Organization lists GPS spoofing, with RF jamming, high-power lasers, EMP and projectile guns, among counter-UAS measures against small UAVs.

Remember · Swarm = many drones acting together on a mission. Counter-drone tools: RF jamming, GPS spoofing, lasers, EMP, projectile guns.

Question and answer: UPSC's provisional GS Paper I (2026, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 1 Oct 2026 (how we verify). Permalink · Report an error

Answer: (a) 1 and 2

The Su-30 MKI is built in India by Hindustan Aeronautics Limited at its Nasik division, and the T-90 Bhishma tank is built in India by Armoured Vehicles Nigam Limited, a Government of India enterprise. The Akula-class submarine the Navy has operated, INS Chakra, was a Russian-built boat taken on lease and is not Indian-made.

• ✓ 1. The Ministry of Defence's 2024 contract for 12 more Su-30MKI aircraft with HAL says they will be manufactured at HAL's Nasik division.
• ✓ 2. Armoured Vehicles Nigam Limited, a Government of India enterprise, lists the T90 Bhishma among the battle tanks in its own product range.
• ✗ 3. The Navy's Akula-class submarine, INS Chakra (ex-K-152 Nerpa), was handed over by the Russian Navy on a 10-year lease (The Times of India); India does not build Akula-class boats.

Remember · Su-30 MKI: built by HAL in India (Nasik). T-90 Bhishma: built by AVNL (Government of India enterprise). Akula-class submarine INS Chakra: leased from Russia, not Indian-built.

Question and answer: UPSC's provisional GS Paper I (2026, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 1 Oct 2026 (how we verify). Permalink · Report an error

Answer: (c) 1 and 2 only

The standard is IS 19445:2025, Bomb Disposal Systems: Performance Evaluation and Requirements, released on 24 December 2025. Its expected benefits include better interoperability of equipment across agencies. It was prepared by a BIS committee with a panel convened by TBRL (DRDO), with Indian stakeholders; no Russian institute is named.

• ✓ 1. IS 19445:2025 was released on National Consumer Day 2025 at Bharat Mandapam, New Delhi, as the Indian Standard for bomb disposal systems.
• ✓ 2. The official release lists improved reliability and interoperability of equipment across agencies among the standard's expected benefits.
• ✗ 3. The standard was developed by TBRL, Chandigarh (DRDO), and BIS at the Ministry of Home Affairs' request, through a BIS committee and a panel convened by TBRL. The official accounts name no Russian institute.

Remember · IS 19445:2025 is the BIS standard for bomb disposal systems (bomb blankets, baskets, inhibitors), developed by TBRL (DRDO) and BIS at the Home Ministry's request.

Question and answer: UPSC's provisional GS Paper I (2026, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (a) 1 and 3 only

Statements 1 and 3 are correct: REEs feed high-technology products such as magnets for EVs and wind turbines, and the National Critical Mineral Mission was launched in 2025. Statement 2 is wrong because China leads mining by a huge margin but India is far behind several other countries, and statement 4 is wrong because there are 17 rare earth elements, not 13.

• ✓ 1. Rare earth magnets are central to electric mobility, renewable energy, electronics and defence applications, and REEs such as dysprosium and neodymium go into wind-turbine magnets.
• ✗ 2. USGS shows China far ahead in 2025 mine production (270,000 tonnes REO), but India (2,900 tonnes) is well behind the United States (51,000), Australia, Burma and Thailand, so India is not second.
• ✓ 3. PIB records that the Government of India launched the NCMM in 2025 to build a robust framework for self-reliance in critical minerals (Cabinet approval was on 29 January 2025).
• ✗ 4. A Ministry of Mines/DAE reply in the Lok Sabha notes that REE has 17 elements, not 13.

Remember · There are 17 rare earth elements (15 lanthanides plus scandium and yttrium). NCMM was launched in 2025. China dominates mining; India is a minor producer.

Question and answer: UPSC's provisional GS Paper I (2026, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error